Commit Graph

551 Commits

Author SHA1 Message Date
Joao Martins
a31fe5daea vfio/common: Separate vfio-pci ranges
QEMU computes the DMA logging ranges for two predefined ranges: 32-bit
and 64-bit. In the OVMF case, when the dynamic MMIO window is enabled,
QEMU includes in the 64-bit range the RAM regions at the lower part
and vfio-pci device RAM regions which are at the top of the address
space. This range contains a large gap and the size can be bigger than
the dirty tracking HW limits of some devices (MLX5 has a 2^42 limit).

To avoid such large ranges, introduce a new PCI range covering the
vfio-pci device RAM regions, this only if the addresses are above 4GB
to avoid breaking potential SeaBIOS guests.

[ clg: - wrote commit log
       - fixed overlapping 32-bit and PCI ranges when using SeaBIOS ]

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Fixes: 5255bbf4ec ("vfio/common: Add device dirty page tracking start/stop")
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:06 +02:00
Avihai Horon
615379764a vfio/migration: Block VFIO migration with background snapshot
Background snapshot allows creating a snapshot of the VM while it's
running and keeping it small by not including dirty RAM pages.

The way it works is by first stopping the VM, saving the non-iterable
devices' state and then starting the VM and saving the RAM while write
protecting it with UFFD. The resulting snapshot represents the VM state
at snapshot start.

VFIO migration is not compatible with background snapshot.
First of all, VFIO device state is not even saved in background snapshot
because only non-iterable device state is saved. But even if it was
saved, after starting the VM, a VFIO device could dirty pages without it
being detected by UFFD write protection. This would corrupt the
snapshot, as the RAM in it would not represent the RAM at snapshot
start.

To prevent this, block VFIO migration with background snapshot.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:06 +02:00
Avihai Horon
bf7ef7a2da vfio/migration: Block VFIO migration with postcopy migration
VFIO migration is not compatible with postcopy migration. A VFIO device
in the destination can't handle page faults for pages that have not been
sent yet.

Doing such migration will cause the VM to crash in the destination:

qemu-system-x86_64: VFIO_MAP_DMA failed: Bad address
qemu-system-x86_64: vfio_dma_map(0x55a28c7659d0, 0xc0000, 0xb000, 0x7f1b11a00000) = -14 (Bad address)
qemu: hardware error: vfio: DMA mapping failed, unable to continue

To prevent this, block VFIO migration with postcopy migration.

Reported-by: Yanghang Liu <yanghliu@redhat.com>
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Tested-by: Yanghang Liu <yanghliu@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:06 +02:00
Avihai Horon
8118349b1b vfio/migration: Fail adding device with enable-migration=on and existing blocker
If a device with enable-migration=on is added and it causes a migration
blocker, adding the device should fail with a proper error.

This is not the case with multiple device migration blocker when the
blocker already exists. If the blocker already exists and a device with
enable-migration=on is added which causes a migration blocker, adding
the device will succeed.

Fix it by failing adding the device in such case.

Fixes: 8bbcb64a71 ("vfio/migration: Make VFIO migration non-experimental")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:06 +02:00
Avihai Horon
5c7a4b6035 vfio/migration: Allow migration of multiple P2P supporting devices
Now that P2P support has been added to VFIO migration, allow migration
of multiple devices if all of them support P2P migration.

Single device migration is allowed regardless of P2P migration support.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:05 +02:00
Avihai Horon
94f775e428 vfio/migration: Add P2P support for VFIO migration
VFIO migration uAPI defines an optional intermediate P2P quiescent
state. While in the P2P quiescent state, P2P DMA transactions cannot be
initiated by the device, but the device can respond to incoming ones.
Additionally, all outstanding P2P transactions are guaranteed to have
been completed by the time the device enters this state.

The purpose of this state is to support migration of multiple devices
that might do P2P transactions between themselves.

Add support for P2P migration by transitioning all the devices to the
P2P quiescent state before stopping or starting the devices. Use the new
VMChangeStateHandler prepare_cb to achieve that behavior.

This will allow migration of multiple VFIO devices if all of them
support P2P migration.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:05 +02:00
Joao Martins
3d4d0f0e06 vfio/migration: Refactor PRE_COPY and RUNNING state checks
Move the PRE_COPY and RUNNING state checks to helper functions.

This is in preparation for adding P2P VFIO migration support, where
these helpers will also test for PRE_COPY_P2P and RUNNING_P2P states.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:05 +02:00
Avihai Horon
5485298ce0 vfio/migration: Move from STOP_COPY to STOP in vfio_save_cleanup()
Changing the device state from STOP_COPY to STOP can take time as the
device may need to free resources and do other operations as part of the
transition. Currently, this is done in vfio_save_complete_precopy() and
therefore it is counted in the migration downtime.

To avoid this, change the device state from STOP_COPY to STOP in
vfio_save_cleanup(), which is called after migration has completed and
thus is not part of migration downtime.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11 08:34:05 +02:00
Alex Williamson
c00aac6f14 vfio/pci: Enable AtomicOps completers on root ports
Dynamically enable Atomic Ops completer support around realize/exit of
vfio-pci devices reporting host support for these accesses and adhering
to a minimal configuration standard.  While the Atomic Ops completer
bits in the root port device capabilities2 register are read-only, the
PCIe spec does allow RO bits to change to reflect hardware state.  We
take advantage of that here around the realize and exit functions of
the vfio-pci device.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Robin Voetter <robin@streamhpc.com>
Tested-by: Robin Voetter <robin@streamhpc.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Tony Krowiak
1360b2ad1f s390x/ap: Wire up the device request notifier interface
Let's wire up the device request notifier interface to handle device unplug
requests for AP.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Link: https://lore.kernel.org/qemu-devel/20230530225544.280031-1-akrowiak@linux.ibm.com/
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Avihai Horon
8af87a3ec7 vfio: Fix null pointer dereference bug in vfio_bars_finalize()
vfio_realize() has the following flow:
1. vfio_bars_prepare() -- sets VFIOBAR->size.
2. msix_early_setup().
3. vfio_bars_register() -- allocates VFIOBAR->mr.

After vfio_bars_prepare() is called msix_early_setup() can fail. If it
does fail, vfio_bars_register() is never called and VFIOBAR->mr is not
allocated.

In this case, vfio_bars_finalize() is called as part of the error flow
to free the bars' resources. However, vfio_bars_finalize() calls
object_unparent() for VFIOBAR->mr after checking only VFIOBAR->size, and
thus we get a null pointer dereference.

Fix it by checking VFIOBAR->mr in vfio_bars_finalize().

Fixes: 89d5202edc ("vfio/pci: Allow relocating MSI-X MMIO")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Zhenzhong Duan
d4a2af747d vfio/migration: Return bool type for vfio_migration_realize()
Make vfio_migration_realize() adhere to the convention of other realize()
callbacks(like qdev_realize) by returning bool instead of int.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Suggested-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Zhenzhong Duan
0520d63c77 vfio/migration: Remove print of "Migration disabled"
Property enable_migration supports [on/off/auto].
In ON mode, error pointer is passed to errp and logged.
In OFF mode, we doesn't need to log "Migration disabled" as it's intentional.
In AUTO mode, we should only ever see errors or warnings if the device
supports migration and an error or incompatibility occurs while further
probing or configuring it. Lack of support for migration shoundn't
generate an error or warning.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Zhenzhong Duan
2b43b2995b vfio/migration: Free resources when vfio_migration_realize fails
When vfio_realize() succeeds, hot unplug will call vfio_exitfn()
to free resources allocated in vfio_realize(); when vfio_realize()
fails, vfio_exitfn() is never called and we need to free resources
in vfio_realize().

In the case that vfio_migration_realize() fails,
e.g: with -only-migratable & enable-migration=off, we see below:

(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,enable-migration=off
0000:81:11.1: Migration disabled
Error: disallowing migration blocker (--only-migratable) for: 0000:81:11.1: Migration is disabled for VFIO device

If we hotplug again we should see same log as above, but we see:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,enable-migration=off
Error: vfio 0000:81:11.1: device is already attached

That's because some references to VFIO device isn't released.
For resources allocated in vfio_migration_realize(), free them by
jumping to out_deinit path with calling a new function
vfio_migration_deinit(). For resources allocated in vfio_realize(),
free them by jumping to de-register path in vfio_realize().

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Fixes: a22651053b ("vfio: Make vfio-pci device migration capable")
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Zhenzhong Duan
3c26c80a0a vfio/migration: Change vIOMMU blocker from global to per device
Contrary to multiple device blocker which needs to consider already-attached
devices to unblock/block dynamically, the vIOMMU migration blocker is a device
specific config. Meaning it only needs to know whether the device is bypassing
or not the vIOMMU (via machine property, or per pxb-pcie::bypass_iommu), and
does not need the state of currently present devices. For this reason, the
vIOMMU global migration blocker can be consolidated into the per-device
migration blocker, allowing us to remove some unnecessary code.

This change also makes vfio_mig_active() more accurate as it doesn't check for
global blocker.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Zhenzhong Duan
adee0da036 vfio/pci: Disable INTx in vfio_realize error path
When vfio realize fails, INTx isn't disabled if it has been enabled.
This may confuse host side with unhandled interrupt report.

Fixes: c5478fea27 ("vfio/pci: Respond to KVM irqchip change notifier")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Alex Williamson
0ddcb39c93 hw/vfio/pci-quirks: Sanitize capability pointer
Coverity reports a tained scalar when traversing the capabilities
chain (CID 1516589).  In practice I've never seen a device with a
chain so broken as to cause an issue, but it's also pretty easy to
sanitize.

Fixes: f6b30c1984 ("hw/vfio/pci-quirks: Support alternate offset for GPUDirect Cliques")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10 09:52:52 +02:00
Zhenzhong Duan
0cc889c882 vfio/pci: Free leaked timer in vfio_realize error path
When vfio_realize fails, the mmap_timer used for INTx optimization
isn't freed. As this timer isn't activated yet, the potential impact
is just a piece of leaked memory.

Fixes: ea486926b0 ("vfio-pci: Update slow path INTx algorithm timer related")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Zhenzhong Duan
357bd7932a vfio/pci: Fix a segfault in vfio_realize
The kvm irqchip notifier is only registered if the device supports
INTx, however it's unconditionally removed in vfio realize error
path. If the assigned device does not support INTx, this will cause
QEMU to crash when vfio realize fails. Change it to conditionally
remove the notifier only if the notify hook is setup.

Before fix:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,xres=1
Connection closed by foreign host.

After fix:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,xres=1
Error: vfio 0000:81:11.1: xres and yres properties require display=on
(qemu)

Fixes: c5478fea27 ("vfio/pci: Respond to KVM irqchip change notifier")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Avihai Horon
8bbcb64a71 vfio/migration: Make VFIO migration non-experimental
The major parts of VFIO migration are supported today in QEMU. This
includes basic VFIO migration, device dirty page tracking and precopy
support.

Thus, at this point in time, it seems appropriate to make VFIO migration
non-experimental: remove the x prefix from enable_migration property,
change it to ON_OFF_AUTO and let the default value be AUTO.

In addition, make the following adjustments:
1. When enable_migration is ON and migration is not supported, fail VFIO
   device realization.
2. When enable_migration is AUTO (i.e., not explicitly enabled), require
   device dirty tracking support. This is because device dirty tracking
   is currently the only method to do dirty page tracking, which is
   essential for migrating in a reasonable downtime. Setting
   enable_migration to ON will not require device dirty tracking.
3. Make migration error and blocker messages more elaborate.
4. Remove error prints in vfio_migration_query_flags().
5. Rename trace_vfio_migration_probe() to
   trace_vfio_migration_realize().

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Avihai Horon
808642a2f6 vfio/migration: Reset bytes_transferred properly
Currently, VFIO bytes_transferred is not reset properly:
1. bytes_transferred is not reset after a VM snapshot (so a migration
   following a snapshot will report incorrect value).
2. bytes_transferred is a single counter for all VFIO devices, however
   upon migration failure it is reset multiple times, by each VFIO
   device.

Fix it by introducing a new function vfio_reset_bytes_transferred() and
calling it during migration and snapshot start.

Remove existing bytes_transferred reset in VFIO migration state
notifier, which is not needed anymore.

Fixes: 3710586caa ("qapi: Add VFIO devices migration stats in Migration stats")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Shameer Kolothum
c174088923 vfio/pci: Call vfio_prepare_kvm_msi_virq_batch() in MSI retry path
When vfio_enable_vectors() returns with less than requested nr_vectors
we retry with what kernel reported back. But the retry path doesn't
call vfio_prepare_kvm_msi_virq_batch() and this results in,

qemu-system-aarch64: vfio: Error: Failed to enable 4 MSI vectors, retry with 1
qemu-system-aarch64: ../hw/vfio/pci.c:602: vfio_commit_kvm_msi_virq_batch: Assertion `vdev->defer_kvm_irq_routing' failed

Fixes: dc580d51f7 ("vfio: defer to commit kvm irq routing when enable msi/msix")
Reviewed-by: Longpeng <longpeng2@huawei.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Alex Williamson
f6b30c1984 hw/vfio/pci-quirks: Support alternate offset for GPUDirect Cliques
NVIDIA Turing and newer GPUs implement the MSI-X capability at the offset
previously reserved for use by hypervisors to implement the GPUDirect
Cliques capability.  A revised specification provides an alternate
location.  Add a config space walk to the quirk to check for conflicts,
allowing us to fall back to the new location or generate an error at the
quirk setup rather than when the real conflicting capability is added
should there be no available location.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Alex Williamson
634f38f0f7 vfio: Implement a common device info helper
A common helper implementing the realloc algorithm for handling
capabilities.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Robin Voetter <robin@streamhpc.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Avihai Horon
745c42912a vfio/migration: Add support for switchover ack capability
Loading of a VFIO device's data can take a substantial amount of time as
the device may need to allocate resources, prepare internal data
structures, etc. This can increase migration downtime, especially for
VFIO devices with a lot of resources.

To solve this, VFIO migration uAPI defines "initial bytes" as part of
its precopy data stream. Initial bytes can be used in various ways to
improve VFIO migration performance. For example, it can be used to
transfer device metadata to pre-allocate resources in the destination.
However, for this to work we need to make sure that all initial bytes
are sent and loaded in the destination before the source VM is stopped.

Use migration switchover ack capability to make sure a VFIO device's
initial bytes are sent and loaded in the destination before the source
stops the VM and attempts to complete the migration.
This can significantly reduce migration downtime for some devices.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Avihai Horon
eda7362af9 vfio/migration: Add VFIO migration pre-copy support
Pre-copy support allows the VFIO device data to be transferred while the
VM is running. This helps to accommodate VFIO devices that have a large
amount of data that needs to be transferred, and it can reduce migration
downtime.

Pre-copy support is optional in VFIO migration protocol v2.
Implement pre-copy of VFIO migration protocol v2 and use it for devices
that support it. Full description of it can be found in the following
Linux commit: 4db52602a607 ("vfio: Extend the device migration protocol
with PRE_COPY").

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Avihai Horon
6cd1fe1159 vfio/migration: Store VFIO migration flags in VFIOMigration
VFIO migration flags are queried once in vfio_migration_init(). Store
them in VFIOMigration so they can be used later to check the device's
migration capabilities without re-querying them.

This will be used in the next patch to check if the device supports
precopy migration.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Avihai Horon
cf53efbbda vfio/migration: Refactor vfio_save_block() to return saved data size
Refactor vfio_save_block() to return the size of saved data on success
and -errno on error.

This will be used in next patch to implement VFIO migration pre-copy
support.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
Joao Martins
6fe4f6c941 hw/vfio: Add number of dirty pages to vfio_get_dirty_bitmap tracepoint
Include the number of dirty pages on the vfio_get_dirty_bitmap tracepoint.
These are fetched from the newly added return value in
cpu_physical_memory_set_dirty_lebitmap().

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Message-Id: <20230530180556.24441-3-joao.m.martins@oracle.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-06-13 11:28:58 +02:00
Zhenzhong Duan
b83b40b614 vfio/pci: Fix a use-after-free issue
vbasedev->name is freed wrongly which leads to garbage VFIO trace log.
Fix it by allocating a dup of vbasedev->name and then free the dup.

Fixes: 2dca1b37a7 ("vfio/pci: add support for VF token")
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-05-24 09:21:22 +02:00
Alex Williamson
b5048a4cbf vfio/pci: Static Resizable BAR capability
The PCI Resizable BAR (ReBAR) capability is currently hidden from the
VM because the protocol for interacting with the capability does not
support a mechanism for the device to reject an advertised supported
BAR size.  However, when assigned to a VM, the act of resizing the
BAR requires adjustment of host resources for the device, which
absolutely can fail.  Linux does not currently allow us to reserve
resources for the device independent of the current usage.

The only writable field within the ReBAR capability is the BAR Size
register.  The PCIe spec indicates that when written, the device
should immediately begin to operate with the provided BAR size.  The
spec however also notes that software must only write values
corresponding to supported sizes as indicated in the capability and
control registers.  Writing unsupported sizes produces undefined
results.  Therefore, if the hypervisor were to virtualize the
capability and control registers such that the current size is the
only indicated available size, then a write of anything other than
the current size falls into the category of undefined behavior,
where we can essentially expose the modified ReBAR capability as
read-only.

This may seem pointless, but users have reported that virtualizing
the capability in this way not only allows guest software to expose
related features as available (even if only cosmetic), but in some
scenarios can resolve guest driver issues.  Additionally, no
regressions in behavior have been reported for this change.

A caveat here is that the PCIe spec requires for compatibility that
devices report support for a size in the range of 1MB to 512GB,
therefore if the current BAR size falls outside that range we revert
to hiding the capability.

Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230505232308.2869912-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-09 09:30:13 -06:00
Avihai Horon
ff180c6bd7 vfio/migration: Skip log_sync during migration SETUP state
Currently, VFIO log_sync can be issued while migration is in SETUP
state. However, doing this log_sync is at best redundant and at worst
can fail.

Redundant -- all RAM is marked dirty in migration SETUP state and is
transferred only after migration is set to ACTIVE state, so doing
log_sync during migration SETUP is pointless.

Can fail -- there is a time window, between setting migration state to
SETUP and starting dirty tracking by RAM save_live_setup handler, during
which dirty tracking is still not started. Any VFIO log_sync call that
is issued during this time window will fail. For example, this error can
be triggered by migrating a VM when a GUI is active, which constantly
calls log_sync.

Fix it by skipping VFIO log_sync while migration is in SETUP state.

Fixes: 758b96b61d ("vfio/migrate: Move switch of dirty tracking into vfio_memory_listener")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230403130000.6422-1-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-09 09:30:13 -06:00
Minwoo Im
2dca1b37a7 vfio/pci: add support for VF token
VF token was introduced [1] to kernel vfio-pci along with SR-IOV
support [2].  This patch adds support VF token among PF and VF(s). To
passthu PCIe VF to a VM, kernel >= v5.7 needs this.

It can be configured with UUID like:

  -device vfio-pci,host=DDDD:BB:DD:F,vf-token=<uuid>,...

[1] https://lore.kernel.org/linux-pci/158396393244.5601.10297430724964025753.stgit@gimli.home/
[2] https://lore.kernel.org/linux-pci/158396044753.5601.14804870681174789709.stgit@gimli.home/

Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Minwoo Im <minwoo.im@samsung.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Link: https://lore.kernel.org/r/20230320073522epcms2p48f682ecdb73e0ae1a4850ad0712fd780@epcms2p4
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-09 09:30:13 -06:00
Richard Henderson
cc37d98bfb *: Add missing includes of qemu/error-report.h
This had been pulled in via qemu/plugin.h from hw/core/cpu.h,
but that will be removed.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-5-richard.henderson@linaro.org>
[AJB: add various additional cases shown by CI]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-15-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
2023-03-22 15:06:57 +00:00
Cédric Le Goater
969dae5448 vfio: Fix vfio_get_dev_region() trace event
Simply transpose 'x8' to fix the typo and remove the ending '8'

Fixes: e61a424f05 ("vfio: Create device specific region info helper")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1526
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/20230303074330.2609377-1-clg@kaod.org
[aw: commit log s/revert/transpose/]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 11:19:07 -07:00
Alex Williamson
8249cffc62 vfio/migration: Rename entry points
Pick names that align with the section drivers should use them from,
avoiding the confusion of calling a _finalize() function from _exit()
and generalizing the actual _finalize() to handle removing the viommu
blocker.

Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/167820912978.606734.12740287349119694623.stgit@omen
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 11:19:07 -07:00
Joao Martins
95b29658b6 vfio/migration: Query device dirty page tracking support
Now that everything has been set up for device dirty page tracking,
query the device for device dirty page tracking support.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-15-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 10:21:22 -07:00
Joao Martins
e46883204c vfio/migration: Block migration with vIOMMU
Migrating with vIOMMU will require either tracking maximum
IOMMU supported address space (e.g. 39/48 address width on Intel)
or range-track current mappings and dirty track the new ones
post starting dirty tracking. This will be done as a separate
series, so add a live migration blocker until that is fixed.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-14-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 10:21:22 -07:00
Joao Martins
b153402a89 vfio/common: Add device dirty page bitmap sync
Add device dirty page bitmap sync functionality. This uses the device
DMA logging uAPI to sync dirty page bitmap from the device.

Device dirty page bitmap sync is used only if all devices within a
container support device dirty page tracking.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-13-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 10:21:22 -07:00
Avihai Horon
6607109f05 vfio/common: Extract code from vfio_get_dirty_bitmap() to new function
Extract the VFIO_IOMMU_DIRTY_PAGES ioctl code in vfio_get_dirty_bitmap()
to its own function.

This will help the code to be more readable after next patch will add
device dirty page bitmap sync functionality.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-12-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 10:21:22 -07:00
Joao Martins
5255bbf4ec vfio/common: Add device dirty page tracking start/stop
Add device dirty page tracking start/stop functionality. This uses the
device DMA logging uAPI to start and stop dirty page tracking by device.

Device dirty page tracking is used only if all devices within a
container support device dirty page tracking.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20230307125450.62409-11-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 10:21:11 -07:00
Joao Martins
62c1b0024b vfio/common: Record DMA mapped IOVA ranges
According to the device DMA logging uAPI, IOVA ranges to be logged by
the device must be provided all at once upon DMA logging start.

As preparation for the following patches which will add device dirty
page tracking, keep a record of all DMA mapped IOVA ranges so later they
can be used for DMA logging start.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-10-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Joao Martins
4ead830848 vfio/common: Add helper to consolidate iova/end calculation
In preparation to be used in device dirty tracking, move the code that
calculate a iova/end range from the container/section.  This avoids
duplication on the common checks across listener callbacks.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-9-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Joao Martins
b92f237635 vfio/common: Consolidate skip/invalid section into helper
The checks are replicated against region_add and region_del
and will be soon added in another memory listener dedicated
for dirty tracking.

Move these into a new helper for avoid duplication.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230307125450.62409-8-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Joao Martins
1cd7fa7adc vfio/common: Use a single tracepoint for skipped sections
In preparation to turn more of the memory listener checks into
common functions, one of the affected places is how we trace when
sections are skipped. Right now there is one for each. Change it
into one single tracepoint `vfio_listener_region_skip` which receives
a name which refers to the callback i.e. region_add and region_del.

Suggested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-7-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Joao Martins
fbc6c92134 vfio/common: Add helper to validate iova/end against hostwin
Move the code that finds the container host DMA window against a iova
range. This avoids duplication on the common checks across listener
callbacks.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230307125450.62409-6-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Avihai Horon
725ccd7e41 vfio/common: Add VFIOBitmap and alloc function
There are already two places where dirty page bitmap allocation and
calculations are done in open code.

To avoid code duplication, introduce VFIOBitmap struct and corresponding
alloc function and use them where applicable.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-5-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Avihai Horon
236e0a45f5 vfio/common: Abort migration if dirty log start/stop/sync fails
If VFIO dirty pages log start/stop/sync fails during migration,
migration should be aborted as pages dirtied by VFIO devices might not
be reported properly.

This is not the case today, where in such scenario only an error is
printed.

Fix it by aborting migration in the above scenario.

Fixes: 758b96b61d ("vfio/migrate: Move switch of dirty tracking into vfio_memory_listener")
Fixes: b6dd6504e3 ("vfio: Add vfio_listener_log_sync to mark dirty pages")
Fixes: 9e7b0442f2 ("vfio: Add ioctl to get dirty pages bitmap during dma unmap")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-4-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Avihai Horon
db9b829b15 vfio/common: Fix wrong %m usages
There are several places where the %m conversion is used if one of
vfio_dma_map(), vfio_dma_unmap() or vfio_get_dirty_bitmap() fail.

The %m usage in these places is wrong since %m relies on errno value while
the above functions don't report errors via errno.

Fix it by using strerror() with the returned value instead.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-3-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00
Avihai Horon
3e2413a652 vfio/common: Fix error reporting in vfio_get_dirty_bitmap()
Return -errno instead of -1 if VFIO_IOMMU_DIRTY_PAGES ioctl fails in
vfio_get_dirty_bitmap().

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-2-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-03-07 07:20:32 -07:00